Abstract:

A radio resource assignment method for a physical channel in an uplink
directed from a mobile apparatus to a base station in a radio
communication system, includes: assigning a contention-based channel and
a scheduled channel according to one of a time division scheme, a
frequency division scheme, and a hybrid scheme of the time division
scheme and the frequency division scheme. In addition, radio resources
are properly assigned to each of the contention-based channel, a common
control channel of the scheduled channel, and a shared data channel of
the scheduled channel.

Claims:

1. A radio resource assignment method for a physical channel in an uplink
directed from a mobile apparatus to a base station in a radio
communication system, comprising:assigning a contention-based channel and
a scheduled channel according to one of a time division scheme, a
frequency division scheme, and a hybrid scheme of the time division
scheme and the frequency division scheme.

2. The radio resource assignment method for the physical channel in the
uplink as claimed in claim 1, comprising:assigning an entire channel band
to the contention-based channel.

3. The radio resource assignment method for the physical channel in the
uplink as claimed in claim 1, comprising:assigning a single frequency
block or a plurality of frequency blocks to the contention-based channel.

4. The radio resource assignment method for the physical channel in the
uplink as claimed in claim 1, comprising:assigning a transmission
frequency band that becomes wide or narrow according to a size of a data
rate to the contention-based channel.

5. The radio resource assignment method for the physical channel in the
uplink as claimed in claim 2, comprising:forming a continuous spectrum in
the assigned frequency band.

6. The radio resource assignment method for the physical channel in the
uplink as claimed in claim 2, comprising:forming a comb-shaped spectrum
in the assigned frequency band.

7. The radio resource assignment method for the physical channel in the
uplink as claimed in claim 1 comprising:assigning an entire channel band
to a common control channel of the scheduled channel.

8. The radio resource assignment method for the physical channel in the
uplink as claimed in claim 1, comprising:assigning a signal frequency
block or a plurality of frequency blocks to a common control channel of
the scheduled channel.

9. The radio resource assignment method for the physical channel in the
uplink as claimed in claim 1, comprising:assigning a transmission
frequency band that becomes wide or narrow according to a size of a data
rate to a common control channel of the scheduled channel.

10. The radio resource assignment method for the physical channel in the
uplink as claimed in claim 7, comprising:forming a continuous spectrum in
the assigned frequency band.

11. The radio resource assignment method for the physical channel in the
uplink as claimed in claim 7, comprising:forming a comb-shaped spectrum
in the assigned frequency band.

12. The radio resource assignment method for the physical channel in the
uplink as claimed in claim 1, comprising:assigning an entire channel band
to a shared data channel of the scheduled channel to perform scheduling
in a time domain.

13. The radio resource assignment method for the physical channel in the
uplink as claimed in claim 1, comprising:performing scheduling in a time
domain by fixing a frequency block in a frequency domain for a shared
data channel of the scheduled channel.

14. The radio resource assignment method for the physical channel in the
uplink as claimed in claim 1, comprising:performing scheduling based on a
frequency block of a frequency domain and a time domain for a shared data
channel of the scheduled channel.

15. The radio resource assignment method for the physical channel in the
uplink as claimed in claim 13, comprising:performing multiplexing in the
frequency block based on frequency division by a comb-shaped spectrum,
normal frequency division, time division or code division.

16. A transmitter for mobile apparatuses, comprising:means that assigns a
contention-based channel and a scheduled channel according to one of a
time division scheme, a frequency division scheme, and a hybrid scheme of
the time division scheme and the frequency division scheme so as to
perform transmission.

17. The transmitter for mobile apparatuses as claimed in claim 16,
comprising:a channel coding unit that performs channel coding for
transmission data;a data modulation unit that modulates the channel-coded
transmission data;a spreading unit that spreads the modulated
transmission data;a symbol repetition unit that repeats symbols of the
spread transmission data;a frequency offset adding unit that provides
frequency offsets for each user to the symbol-repeated transmission
data;a data modulation/spreading factor/channel coding control unit that
controls the channel coding unit, the data modulation unit and the
spreading unit according to a channel type of the transmission data and
to MCS information for the user provided from a base station; anda
frequency diversity/scheduling unit that controls the symbol repetition
unit and the frequency offset adding unit according to the channel type
of the transmission data, announcement information, provided from the
base station, of radio resource assignment to each physical channel and
scheduling result information for the user.

18. The transmitter for mobile apparatuses as claimed in claim 16,
comprising:a channel coding unit that performs channel coding for
transmission data;a data modulation unit that modulates the channel-coded
transmission data;a spreading unit that spreads the modulated
transmission data;a FFT unit that converts the spread transmission data
into signals of a frequency domain;a frequency domain signal generation
unit that maps the transmission data converted to the frequency domain to
the frequency domain;an IFFT unit that converts the transmission data
mapped to the frequency domain to signals of a time domain;a data
modulation/spreading factor/channel coding control unit that controls the
channel coding unit, the data modulation unit and the spreading unit
according to a channel type of the transmission data and to MCS
information for the user provided from the base station; anda frequency
diversity/scheduling unit that controls the frequency domain signal
generation unit according to the channel type of the transmission data,
announcement information, provided from the base station, of radio
resource assignment to each physical channel and scheduling result
information for the user.

19. The transmitter for mobile apparatuses as claimed in claim 16,
comprising:a channel coding unit that performs channel coding for
transmission data;a data modulation unit that modulates the channel-coded
transmission data;a spreading unit that spreads the modulated
transmission data;a serial/parallel conversion unit that converts the
spread transmission data into parallel signals;a frequency domain signal
generation unit that maps the transmission data converted to the parallel
signals to the frequency domain;an IFFT unit that converts the
transmission data mapped to the frequency domain to signals of a time
domain;a data modulation/spreading factor/channel coding control unit
that controls the channel coding unit, the data modulation unit and the
spreading unit according to a channel type of the transmission data and
to MCS information for the user provided from the base station; anda
frequency diversity/scheduling unit that controls the frequency domain
signal generation unit according to the channel type of the transmission
data, announcement information, provided from the base station, of radio
resource assignment to each physical channel and scheduling result
information for the user.

20. The transmitter for mobile apparatuses as claimed in claim 16,
comprising:a channel coding unit that performs channel coding for
transmission data;a data modulation unit that modulates the channel-coded
transmission data;a spreading unit that spreads the modulated
transmission data;a switch unit that selects and branches the spread
transmission data;a FFT unit that converts the selected and branched
transmission data into signals of a frequency domain;a serial/parallel
conversion unit that converts the selected and branched transmission data
into parallel signals;a frequency domain signal generation unit that maps
output signals of the FFT unit or the serial/parallel conversion unit to
the frequency domain;an IFFT unit that converts the transmission data
mapped to the frequency domain to signals of a time domain;a data
modulation/spreading factor/channel coding control unit that controls the
channel coding unit, the data modulation unit and the spreading unit
according to a channel type of the transmission data and to MCS
information for the user provided from the base station; anda frequency
diversity/scheduling unit that controls the frequency domain signal
generation unit according to the channel type of the transmission data,
announcement information, provided from the base station, of radio
resource assignment to each physical channel and scheduling result
information for the user.

Description:

TECHNICAL FIELD

[0001]The present invention relates to a radio resource assignment method
for a physical channel in an uplink directed from a mobile apparatus to a
base station in a mobile radio communication system, and relates to a
transmitter for mobile apparatuses.

BACKGROUND ART

[0002]Development is being carried out for a mobile radio communication
system of a next generation that is far superior to the capability of a
third generation mobile radio communication system for which service has
already started. This next generation mobile radio communication system
aims transmission with higher speed and larger capacity, inter-system
interconnection based on IP (Internet Protocol) networking, and the like.

[0003][Patent document 1] WO2003/041438 (International Publication)

DISCLOSURE OF THE INVENTION

Problem to be Solved by the Invention

[0004]It is predicted that a channel band that is 5 MHz in the third
generation W-CDMA (Wideband-Code Division Multiple Access) will be
enlarged to about 20 MHz in the next generation radio communication
system, so that it is desired to effectively assign a wide channel band
to physical channels. In this case, it is necessary to consider frequency
diversity (improvement of communication quality under frequency selective
fading environment due to diversifying a signal to wide band) and
multiuser diversity (improvement of communication quality under frequency
selective fading environment due to assigning a signal of each user to a
frequency block having a good channel status). By the way, it is
effective to diversify a signal to wide band for obtaining the frequency
diversity effect, but on the other hand, there is a problem in that, when
a data rate of transmission data is low, transmission power density
becomes small so that channel estimation accuracy is deteriorated. Thus,
it becomes necessary to assign radio resources according to data rates.

[0005]On the other hand, in an uplink directed from a mobile apparatus to
a base station in the mobile radio communication system, there is an
uplink contention-based channel by which data transmission is performed
irregularly from the mobile apparatus. Since a signal by this
contention-based channel is a prerequisite for performing transmission of
packet data by an uplink scheduled channel based on scheduling in the
base station side, it is necessary that errors due to interference are
small and that the signal is effectively transmitted to the base station
side within a short time. As to such a signal directed from the mobile
apparatus to the base station, the patent document 1 discloses a
technique (power ramping technique) for decreasing interference to other
mobile apparatuses by gradually increasing transmission power to send a
signal intermittently until the base station side acknowledges receipt.
According to this power ramping technique, since transmission is
performed a plurality of times until the base station side acknowledges
receipt, there is a problem in that transfer of reservation of scheduling
and the like delays so that transmission of packet data after that
delays.

[0006]In addition, in a conventional W-CDMA, as shown in FIG. 1,
multiplexing is performed by CDM (Code Division Multiplex) in which the
contention-based channel and the scheduled channel are separated by
different spreading codes. But, deterioration due to inter-code
interference is a problem. This is an unavoidable selection since
priority is given to an advantage of using the entire channel band for
the contention-based channel and the scheduled channel for obtaining the
frequency diversity effect under a constraint that the channel band is 5
MHz.

[0007]The present invention is proposed in view of the above-mentioned
points, and the object is to provide a radio resource assignment method
for a physical channel in an uplink and a transmitter for mobile
apparatuses that can properly perform radio resource assignment for a
physical channel in an uplink directed to a mobile apparatus to a base
station in a mobile radio communication system under an environment of
the next generation mobile radio communication system.

Means for Solving the Problem

[0008]To solve the above problem, in the present invention, as described
in claim 1, a radio resource assignment method for a physical channel in
an uplink directed from a mobile apparatus to a base station in a radio
communication system, includes:

[0009]assigning a contention-based channel and a scheduled channel
according to one of a time division scheme, a frequency division scheme,
and a hybrid scheme of the time division scheme and the frequency
division scheme.

[0010]In addition, as described in claim 2, the radio resource assignment
method for the physical channel in the uplink as claimed in claim 1, may
include:

[0011]assigning an entire channel band to the contention-based channel.

[0012]In addition, as described in claim 3, the radio resource assignment
method for the physical channel in the uplink as claimed in claim 1 may
include:

[0013]assigning a single frequency block or a plurality of frequency
blocks to the contention-based channel.

[0014]In addition, as described in claim 4, the radio resource assignment
method for the physical channel in the uplink as claimed in claim 1 may
include:

[0015]assigning a transmission frequency band that becomes wide or narrow
according to a size of a data rate to the contention-based channel.

[0016]In addition, as described in claim 5, the radio resource assignment
method for the physical channel in the uplink as claimed in claim 2 may
include:

[0017]forming a continuous spectrum in the assigned frequency band.

[0018]In addition, as described in claim 6, the radio resource assignment
method for the physical channel in the uplink as claimed in claim 2 may
include:

[0019]forming a comb-shaped spectrum in the assigned frequency band.

[0020]In addition, as described in claim 7, the radio resource assignment
method for the physical channel in the uplink as claimed in claim 1 may
include:

[0021]assigning an entire channel band to a common control channel of the
scheduled channel.

[0022]In addition, as described in claim 8, the radio resource assignment
method for the physical channel in the uplink as claimed in claim 1 may
include:

[0023]assigning a signal frequency block or a plurality of frequency
blocks to a common control channel of the scheduled channel.

[0024]In addition, as described in claim 9, the radio resource assignment
method for the physical channel in the uplink as claimed in claim 1 may
include:

[0025]assigning a transmission frequency band that becomes wide or narrow
according to a size of a data rate to a common control channel of the
scheduled channel.

[0026]In addition, as described in claim 10, the radio resource assignment
method for the physical channel in the uplink as claimed in claim 7 may
include:

[0027]forming a continuous spectrum in the assigned frequency band.

[0028]In addition, as described in claim 11, the radio resource assignment
method for the physical channel in the uplink as claimed in claim 7 may
include:

[0029]forming a comb-shaped spectrum in the assigned frequency band.

[0030]In addition, as described in claim 12, the radio resource assignment
method for the physical channel in the uplink as claimed in claim 1 may
include:

[0031]assigning an entire channel band to a shared data channel of the
scheduled channel to perform scheduling in a time domain.

[0032]In addition, as described in claim 13, the radio resource assignment
method for the physical channel in the uplink as claimed in claim 1 may
include:

[0033]performing scheduling in a time domain by fixing a frequency block
in a frequency domain for a shared data channel of the scheduled channel.

[0034]In addition, as described in claim 14, the radio resource assignment
method for the physical channel in the uplink as claimed in claim 1 may
include:

[0035]performing scheduling based on a frequency block of a frequency
domain and a time domain for a shared data channel of the scheduled
channel.

[0036]In addition, as described in claim 15, the radio resource assignment
method for the physical channel in the uplink as claimed in claim 13,
comprising:

[0037]performing multiplexing in the frequency block based on frequency
division by a comb-shaped spectrum, normal frequency division, time
division or code division.

[0038]In addition, as described in claim 16, a transmitter for mobile
apparatuses includes:

[0039]means that assigns a contention-based channel and a scheduled
channel according to one of a time division scheme, a frequency division
scheme, and a hybrid scheme of the time division scheme and the frequency
division scheme so as to perform transmission.

[0040]In addition, as described in claim 17, the transmitter for mobile
apparatuses as claimed in claim 16 may include:

[0046]a data modulation/spreading factor/channel coding control unit that
controls the channel coding unit, the data modulation unit and the
spreading unit according to a channel type of the transmission data and
to MCS information for the user provided from a base station; and

[0047]a frequency diversity/scheduling unit that controls the symbol
repetition unit and the frequency offset adding unit according to the
channel type of the transmission data, announcement information, provided
from the base station, of radio resource assignment to each physical
channel and scheduling result information for the user.

[0048]In addition, as described in claim 18, the transmitter for mobile
apparatuses as claimed in claim 16 may include:

[0052]a FET unit that converts the spread transmission data into signals
of a frequency domain;

[0053]a frequency domain signal generation unit that maps the transmission
data converted to the frequency domain to the frequency domain;

[0054]an IFFT unit that converts the transmission data mapped to the
frequency domain to signals of a time domain;

[0055]a data modulation/spreading factor/channel coding control unit that
controls the channel coding unit, the data modulation unit and the
spreading unit according to a channel type of the transmission data and
to MCS information for the user provided from the base station; and

[0056]a frequency diversity/scheduling unit that controls the frequency
domain signal generation unit according to the channel type of the
transmission data, announcement information, provided from the base
station, of radio resource assignment to each physical channel and
scheduling result information for the user.

[0057]In addition, as described in claim 19, the transmitter for mobile
apparatuses as claimed in claim 16 may include:

[0062]a frequency domain signal generation unit that maps the transmission
data converted to the parallel signals to the frequency domain;

[0063]an IFFT unit that converts the transmission data mapped to the
frequency domain to signals of a time domain;

[0064]a data modulation/spreading factor/channel coding control unit that
controls the channel coding unit, the data modulation unit and the
spreading unit according to a channel type of the transmission data and
to MCS information for the user provided from the base station; and

[0065]a frequency diversity/scheduling unit that controls the frequency
domain signal generation unit according to the channel type of the
transmission data, announcement information, provided from the base
station, of radio resource assignment to each physical channel and
scheduling result information for the user.

[0066]In addition, as described in claim 20, the transmitter for mobile
apparatuses as claimed in claim 16 may include:

[0073]a frequency domain signal generation unit that maps output signals
of the FFT unit or the serial/parallel conversion unit to the frequency
domain;

[0074]an IFFT unit that converts the transmission data mapped to the
frequency domain to signals of a time domain;

[0075]a data modulation/spreading factor/channel coding control unit that
controls the channel coding unit, the data modulation unit and the
spreading unit according to a channel type of the transmission data and
to MCS information for the user provided from the base station; and

[0076]a frequency diversity/scheduling unit that controls the frequency
domain signal generation unit according to the channel type of the
transmission data, announcement information, provided from the base
station, of radio resource assignment to each physical channel and
scheduling result information for the user.

EFFECT OF THE INVENTION

[0077]In the radio resource assignment method for the physical channel in
the uplink, and the transmitter for mobile apparatus use of the present
invention, code separation is not adopted for dividing between the
contention-based channel and the scheduled channel, frequency diversity
and multiuser diversity are effectively applied, the power ramping
technique is not adopted, assignment of radio resources according to data
rates and the like is performed. Thus, radio resource assignment for
physical channel in the uplink directed from a mobile apparatus to a base
station in a mobile radio communication system can be properly performed
under an environment of a next generation mobile radio communication
system.

BRIEF DESCRIPTION OF THE DRAWINGS

[0078]FIG. 1 is a schematic diagram of multiplexing of a contention-based
channel and a scheduled channel by CDM in conventional W-CDMA;

[0079]FIG. 2 is a diagram showing examples of physical channels in an
uplink;

[0080]FIG. 3 is a diagram showing examples of a method for multiplexing
the contention-based channel and the scheduled channel;

[0081]FIG. 4 is a diagram showing examples of a radio resource assignment
method for the contention-based channel;

[0082]FIG. 5 is a diagram showing examples of a radio resource assignment
method for a common control channel of scheduled channels;

[0083]FIG. 6 is a diagram showing examples of a radio resource assignment
method for a shared data channel of scheduled channels;

[0084]FIG. 7 is a diagram showing examples of assignment in a case where
the frequency domain chunk is fixed and scheduling is performed in a time
domain;

[0085]FIG. 8 is a diagram showing examples of converting a chunk to
sub-chunks when performing scheduling in the time domain by fixing the
chunk of the frequency domain;

[0086]FIG. 9 is a diagram showing examples of assignment when performing
scheduling in the frequency domain and the time domain;

[0087]FIG. 10 is a diagram showing examples of converting a chunk to
sub-chunks when performing scheduling in the frequency domain and the
time domain;

[0088]FIG. 11 is a diagram showing a configuration example of a
transmitter for mobile apparatuses based on time domain processing
supporting a single carrier scheme;

[0089]FIG. 12 shows a configuration example of a transmitter for mobile
apparatuses using frequency domain processing supporting the single
carrier scheme;

[0090]FIG. 13 is a diagram showing a configuration example of a
transmitter for mobile apparatuses supporting the multi-carrier scheme;

[0091]FIG. 14 is a diagram showing an configuration example of a
transmitter for mobile apparatuses supporting the both schemes of the
single carrier scheme and the multi-carrier scheme.

[0107]In the following, preferred embodiments of the present invention are
described with reference drawings.

[0108]FIG. 2 is a diagram showing examples of physical channels in the
uplink. In FIG. 2, the physical channel in the uplink can be largely
classified to the contention-based channel and the scheduled channel. The
contention-based channel includes a random access channel that is a
channel used when sending short data or an upper control signal, a
reservation packet channel that is a channel for sending reservation
information for scheduling before transmitting the scheduled data
channel, or the like.

[0109]The scheduled channel is classified to a channel for which
scheduling is performed according to channel status and a channel for
which scheduling is performed irrespective of channel status. The channel
for which scheduling is performed according to channel status includes a
shared data channel that is a channel for transmitting packet data. In
addition, the channel for which scheduling is performed irrespective of
channel status includes a common control channel that is a channel for
transmitting control information. But, when fixed assignment is
performed, the common control channel may be considered to be an
individual control channel.

[0110]FIG. 3 is a diagram showing examples of methods for multiplexing the
contention-based channel and the scheduled channel. FIG. 3(a) shows a
case for multiplexing a contention-based channel Ch1 and a scheduled
channel Ch2 by assigning radio resources in a time division multiplexing
(TDM) scheme. FIG. 3(b) shows a case for multiplexing a contention-based
channel Ch1 and a scheduled channel Ch2 by assigning radio resources in a
frequency division multiplexing (FDM) scheme. FIG. 3(c) shows a case for
multiplexing a contention-based channel Ch1 and a scheduled channel Ch2
by assigning radio resources in a hybrid scheme of the time division
multiplexing scheme and the frequency division multiplexing scheme. As
mentioned before, in the conventional W-CDMA, since multiplexing is
performed by CDM, deterioration due to inter-code interference is a
problem. But, by adopting the time division scheme, the frequency
division scheme or the hybrid scheme of the time division scheme and the
frequency division scheme, signals can be completely separated in time or
in frequency, so that such a problem is eliminated. By the way, in the
cases of FIGS. 3(b) and (c), frequency band of the contention-based
channel Ch1 and the scheduled channel Ch2 is decreased compared with the
case of FIG. 3(a) in which the entire channel band is used continuously.
But, since the channel band that is 5 MHz in the conventional W-CDMA is
increased to about 20 MHz in the next generation mobile radio
communication system, enough bandwidth for obtaining the frequency
diversity effect can be kept. In addition, as shown in FIGS. 3(b) and
(c), since the contention-based channel Ch1 and the scheduled channel Ch2
are distributed over the entire channel band, enough frequency diversity
effect can be obtained also in this point.

[0111]By the way, the present invention is not limited to any one of a
single carrier scheme such as DS-CDMA (Direct Sequence Code Division
Multiple Access), IFDMA (Interleaved Frequency Division Multiple Access),
VSCRF-CDMA (Variable Spreading and Chip Repetition Factors--Code Division
Multiple Access), etc. and a multi-carrier scheme such as OFDM
(Orthogonal Frequency Division Multiplexing), Spread OFDM, MC-CDMA
(Multi-Carrier Code Division Multiple Access) and VSF-Spread OFDM
(Variable Spreading Factor--Spread Orthogonal Frequency Division
Multiplexing), etc., but the present invention can be applied to both of
the schemes.

[0112]Next, FIG. 4 is a diagram showing examples of radio resource
assignment methods for the contention-based channel. FIGS. 4(a) and (b)
show cases of assigning an entire channel band to the contention-based
channel. In FIG. 4(a), a continuous spectrum is formed in the assigned
frequency band, and in FIG. 4(b), a comb-shaped spectrum is formed in the
assigned frequency band. In the case of the continuous spectrum shown in
FIG. 4(a), contention is performed by CDMA and the like, and in the case
of the comb-shaped spectrum shown in FIG. 4(b), contention is performed
FDMA and CDMA and the like by shifting a position of the comb teeth on
the frequency domain. In addition, FIGS. 4(c) and (d) show cases where a
frequency block formed by one or more chunks is assigned to the
contention-based channel. FIG. 4(c) shows a case forming a continuous
spectrum on the assigned frequency band, and FIG. 4(d) shows a case
forming a comb-shaped spectrum on the assigned frequency band. Also in
this case, in the case of the continuous spectrum shown in FIG. 4(c),
contention is performed by CDMA and the like, and in the case of the
comb-shaped spectrum shown in FIG. 4(d), contention is performed by FDMA
and CDMA and the like.

[0113]As mentioned before, since the signal by the contention-based
channel is a prerequisite for transmission, after the signal, of packet
data by the scheduled channel based on scheduling in the base station
side, the signal needs to have few errors due to interference and needs
to be effectively transmitted to the base station side within a short
period. In the cases of FIGS. 4(a) and (b), since the signal is
distributed over the entire channel band, large frequency diversity
effect can be obtained and variation of received signals decreases so
that stable communication becomes available. Therefore, it becomes
possible to decrease transmission power density, adoption of the power
ramping technique that is conventionally performed can be eliminated or
decreased, so that occurrence of delay due to the power ramping technique
can be avoided.

[0114]By the way, in the cases of FIGS. 4(c) and (d), frequency band of
the contention-based channel is decreased compared with the case of FIGS.
4(a) and (b) in which the entire channel band is used. But, since the
channel band that is 5 MHz in the conventional W-CDMA is increased to
about 20 MHz in the next generation mobile radio communication system,
enough bandwidth for obtaining frequency diversity can be kept.

[0115]In addition, as shown in FIGS. 4(b) and (d), interference can be
decreased by FDM by forming the comb-shaped spectrum and shifting
frequencies from other users (mobile apparatuses).

[0116]In addition, FIGS. 4(a) and (b) are advantageous when a data rate of
transmission data is large, and FIGS. 4(c) and (d) are advantageous when
a data rate of the transmission data is small. That is, when the data
rate of transmission data is small, transmission power density becomes
small according to the cases of FIGS. 4(a) and (b) so that there is a
problem in that channel estimation accuracy when receiving deteriorates.
But, in such a case, deterioration of channel estimation accuracy can be
prevented by narrowing frequency band so as not to use unnecessary large
bandwidth as shown in FIGS. 4(c) and (d).

[0117]FIG. 5 is a diagram showing an example of a radio resource
assignment method for a common control channel of scheduled channels. As
shown in the diagram, radio resource assignment similar to that of the
before mentioned case of the contention-based channel shown in FIG. 4 is
performed. That is, the common control channel is essential for adaptive
control and ARQ (Automatic Repeat reQuest) according to channel status,
low block error rate (BLER) is required, and ARQ cannot be applied to the
common control channel itself. Thus, stability by the frequency diversity
effect is valued. By the way, based on tradeoff between required block
error rate and channel estimation accuracy, FIGS. 5(a) and (b) can be
adopted when a low block error rate is required, and FIGS. 5(c) and (d)
can be adopted when a required block error rate is not so low.

[0118]FIG. 6 is a diagram showing examples of radio resource assignment
methods for a shared data channel of scheduled channels. FIG. 6(a) shows
a case where the entire channel band is assigned to the shared data
channel of scheduled channels to perform scheduling for users #1, #2, #3
. . . in a time domain. In this case, although maximum frequency
diversity effect can be obtained, multiuser diversity effect is small. By
the way, a pilot transmitted by an uplink for CQI measurement is for the
entire channel band.

[0119]FIG. 6(b) shows a case for performing scheduling in the time domain
by fixing a chunk in the frequency domain for the shared data channel of
scheduled channels (including a case where equal to or more than two
chunks are fixedly assigned to a user of large data). In this case, the
multiuser diversity effect is obtained only in the time domain. As a
frequency band of the chunk, large sized one is required in order to be
able to accommodate the user of large data. For example, a band such as
1.25 MHz, 5 MHz, 10 MHz, and 20 MHz can be supposed. By the way, the
pilot transmitted by the uplink for CQI measurement becomes one for a
band assigned beforehand.

[0120]FIG. 6(c) shows a case for performing scheduling using chunks of the
frequency domain and the time domain for the shared data channel of
scheduled channels. In this case, large multiuser diversity effect can be
obtained for both of the frequency domain and the time domain. As a
frequency band of the chunk, a small sized one is required for obtaining
the multiuser diversity effect. For example, a band such as 0.3125 MHz,
0.625 MHz, 1.25 MHz, 2.5 MHz, 5 MHz, 10 MHz, and 20 MHz can be supposed.
By the way, a pilot transmitted by the uplink for CQI measurement becomes
one for the entire channel band since it is unknown which frequency band
is assigned in the scheduling.

[0121]FIG. 7 is a diagram showing an example of assignment in a case,
shown in FIG. 6(b), in which the frequency domain chunk is fixed and
scheduling is performed in the time domain. FIG. 7(a) shows a status in
which users are scheduled be assigned to the chunks C1-C4 in the
frequency direction respectively. FIG. 7(b) shows a status in which
adjacent chunks C1 and C2 are scheduled to be assigned to a same user,
and shows a status in which a center frequency of a radio parameter is
shifted to a center of the two chunks C1 and C2 to double the bandwidth
so that the two chunks operate in the same way as one chunk. Of course,
it is possible to cause the chunk as two chunks. FIG. 7(c) shows a status
in which separated chunks C1 and C3 are scheduled to be assigned to a
same user.

[0122]FIG. 8 is a diagram showing an example of converting a chunk to
sub-chunks when performing scheduling in the time domain by fixing the
chunk of the frequency domain as shown in FIG. 6(b). That is, since a
band of the chunk (the figure shows 5 MHz as an example) cannot be used
effectively by assigning a user in units of a chunk when the data rate is
low, a plurality of users are multiplexed into a chunk. FIG. 8(a) shows
an example in which multiplexing is performed by dividing an individual
chunk C into frequencies using the comb-shaped spectrum. In this case,
when a band corresponding to a tooth of the comb becomes too small, it
becomes more likely to be affected by phase noise. Thus, it is necessary
to pay attention to the smallest size. In addition, FIG. 8(b) shows an
example in which multiplexing is performed by normal frequency division.
By the way, instead of the comb-shaped spectrum or the normal frequency
division, multiplexing may be performed using time division or code
division.

[0123]FIG. 9 shows a diagram showing examples of assignment when
performing scheduling in the frequency domain and the time domain. FIG.
9(a) shows a status in which different users are scheduled to be assigned
to chunks C1-C16 respectively in the frequency direction. FIG. 9(b) shows
a status in which a same user is scheduled to be assigned to consecutive
chunks C1-C8. In the case, a center frequency of the radio parameter is
shifted to a center of the chunks C1-C8 and an eight times bandwidth is
used such that it operates in the same way as operation of one chunk. Of
course, it is possible to cause it to operate as eight chunks. FIG. 9(c)
shows a state in which separated chunks C1, C3, C4, C7, C10, C12, C15 and
C16 are scheduled to be assigned to a same user.

[0124]FIG. 10 is a diagram showing examples of converting a chunk to
sub-chunks when performing scheduling in the frequency domain and the
time domain as shown in FIG. 6(c). Also in this case, since a band of the
chunk (the figure shows 1.25 MHz as an example) cannot be used
effectively by assigning users in units of a chunk when the data rate is
low, a plurality of users are multiplexed into a chunk. FIG. 10(a) shows
an example in which multiplexing is performed by dividing an individual
chunk C into frequencies using the comb-shaped spectrum. In this case,
when a band corresponding to a tooth of the comb becomes too small, it
becomes more likely to be affected by phase noise. Thus, it is necessary
to pay attention to a smallest size. In addition, FIG. 10(b) shows an
example in which multiplexing is performed by normal frequency division.
By the way, instead of the comb-shaped spectrum or normal frequency
division, multiplexing may be performed using time division or code
division.

[0125]Next, FIG. 11 is a diagram showing a configuration example of a
transmitter for mobile apparatuses based on time domain processing
corresponding to a single carrier scheme. In FIG. 11, the transmitter for
mobile apparatuses includes a transmission data generation unit 101 for
generating transmission data, a channel coding unit 102 for performing
channel coding on transmission data, a data modulation unit 103 for
modulating the channel coded transmission data, and a spreading unit 104
for performing spreading on the modulated transmission data. In addition,
the transmitter includes a symbol repetition unit 105 for repeating
symbols (chips) of the spread transmission data, a frequency offset
adding unit 106 for providing a frequency offset of each user to
transmission data in which symbols are repeated, and a CP/ZP adding unit
107 for adding CP (Cyclic Prefix) or ZP (Zero Padding) as a guard
interval to the transmission data to which the frequency offset is added.
An output signal of the CP/ZP adding unit 107 is provided to a RF (Radio
Frequency) transmission unit via filtering not shown in the diagram, and
is transmitted.

[0126]In addition, the transmitter includes, as control units, a data
modulation/spreading factor/channel coding control unit 108 for
controlling the channel coding unit 102, the data modulation unit 103 and
the spreading unit 104 according to a channel type of the transmission
data and MCS (Modulation and Coding Scheme) information for the user
provided from the base station, and a frequency diversity/scheduling
control unit 109 for controlling the symbol repetition unit 105 and the
frequency offset adding unit 106 according to the channel type of the
transmission data, announcement information, provided from the base
station, of radio resource assignment to each physical channel, and
scheduling result information for the user.

[0127]In the operation, the transmitter generates a transmission signal by
performing radio resource assignment according to the multiplexing method
shown in FIG. 3, and further, generates a transmission signal by
assigning radio resources for each channel as shown in FIGS. 4-6 under
control of the data modulation/spreading factor/channel coding control
unit 108 and the frequency diversity/scheduling control unit 109
according to a channel type of transmission data, that is, according to
whether it is the contention-based channel or the scheduled channel, in
addition, according to whether it is the common control channel or the
shared data channel when the type is the scheduled channel.

[0128]In this operation, the symbol repetition unit 105 compresses chips
that are output signals from the spreading unit 104 into each block every
Q chips, and repeats it CRF (Chip Repetition Factor) times. When CRF=1
(when repetition is not performed), the continuous spectrum shown in
FIGS. 4(a) (c) and FIGS. 5(a) (c) is formed. When CRF>1, the
comb-shaped spectrum shown in FIGS. 4(b)(d) and FIGS. 5(b) (d) is formed.

[0129]FIG. 12 shows a configuration example of a transmitter for mobile
apparatuses using frequency domain processing supporting the single
carrier scheme. Although comb-shaped spectrum is formed by time domain
processing in FIG. 11, same processing can be performed by frequency
domain processing in this configuration of FIG. 12. In FIG. 12, the
configuration of the transmitter for mobile apparatuses is different from
one shown in FIG. 11, in that, instead of the symbol repeating unit 105
and the frequency offset adding unit 106 in FIG. 11, the transmitter is
provided with a Q point FFT unit 110 for converting the spread
transmission data into a signal in the frequency domain, a frequency
domain signal generation unit 111 for mapping the transmission data that
has been converted into the frequency domain to the frequency domain, and
a Nsub point IFFT unit 112 for converting the transmission data mapped to
the frequency domain into signals of the time domain, and that the
frequency domain signal generation unit 111 is controlled by the
frequency diversity/scheduling control unit 109, and other configuration
is the same.

[0130]In this configuration, the Q point FFT unit 110 converts the spread
transmission data into Q signals of the frequency domain. The frequency
domain signal generation unit 111 performs rate conversion to enlarge a
frame to a number of sub-carriers Nsub (=QxCRF), and provides frequency
offsets for each user and add "0" to parts other than parts assigned to
the users. Then, the Nsub point IFFT unit 112 performs inverse Fourier
transform from the frequency domain signals of the number of sub-carriers
Nsub to convert the signals into time domain signals. When CRF=1
(Nsub-Q), the continuous spectrum shown in FIGS. 4(a) (c) and FIGS. 5(a)
(c) is formed, and when CRF>1, the comb-shaped spectrum shown in FIGS.
4(b) (d) and FIGS. 5(b) (d) is formed, which are the same as the
before-mentioned example.

[0131]Next, FIG. 13 is a diagram showing a configuration example of a
transmitter for mobile apparatuses supporting a multi-carrier scheme. In
FIG. 13, the configuration of the transmitter for mobile apparatuses is
different from that of FIG. 12 in that, instead of the Q point FFT unit
111 and the frequency domain signal generation unit 111 of FIG. 12, the
transmitter is provided with a S/P conversion unit 113 for converting
spread transmission data (serial signal) into parallel signals and a
frequency domain signal generation unit 114 for mapping the transmission
data converted into the parallel signals into the frequency domain, and
that the frequency domain signal generation unit 114 is controlled by the
frequency diversity/scheduling control unit 109. Other configuration is
the same.

[0132]In this configuration, the S/P conversion unit of FIG. 13 converts
the spread transmission data to Nsub signals and passes them to the
frequency domain signal generation unit 114. In mapping to sub-carriers
in the frequency domain signal generation unit 114, when the transmission
signal of the user is continuously mapped, the continuous spectrum shown
in FIGS. 4(a) (c) and FIGS. 5(a) (c) is formed. When the transmission
data is mapped at predetermined intervals, the comb-shaped spectrum is
formed as shown in FIGS. 4(b) (d) and FIGS. 5(b) (d).

[0133]Next, FIG. 14 is a diagram showing an configuration example of a
transmitter for mobile apparatuses supporting the both schemes of the
single carrier scheme and the multi-carrier scheme. This configuration is
a hybrid of the configuration of the signal carrier scheme shown in FIG.
12 and the configuration of the multi-carrier scheme shown in FIG. 13,
and it is provided with a switch unit 115, after the spreading unit 104,
for selecting and branching the spread transmission data to the Q point
FFT unit 110 and the S/P conversion unit 113.

[0134]The operation is the same as that of the single carrier scheme shown
in FIG. 12 in a state when the switch unit 115 selects the Q point FFT
unit 110 side, and the operation is the same as that of the multi-carrier
scheme shown in FIG. 13 in a state when the switch unit 115 selects the
S/P conversion unit 113 side.

[0135]As mentioned above, the present invention is described by preferred
embodiments of the present invention. Although the present invention is
described by showing particular concrete examples, it is apparent that
variations and modifications may be made for these concrete examples
without departing from the wide effect and scope of the present invention
defined in the claims. That is, the present invention should not be
interpreted to be limited by details of the concrete examples and the
attached drawings.

[0136]The present international application claims priority based on
Japanese patent application No. 2005-105498, filed in the JPO on Mar. 31,
2005, the entire contents of which are incorporated herein by reference.